Alright, so I've had my Wii for probably two and a half years now, and I'm just now having problems with it.
I was playing Mario Party 2 off the VC with some friends last night when the game froze. Subsequently, the Wii turned itself off. Immediately upon turning it on again, the Wii turned itself off.
Upon trying again half an hour later after cleaning the fans out with canned air (figuring that was the issue), the Wii worked fine, to the point where I played about an hour of games. Figured everything was fixed. Tried to turn it on again this morning, and it's turning itself off again immediately during the load-up to the Wii menu.
I'm going to keep it unplugged for a good day now and see if there's any relation there, but is my Wii faulty now?
EDIT: I would like to append this post with more information that I have found.
I was playing a Gamecube game for 40 minutes just now when the Wii shut off. Upon googling the problem more, this can be a number of issues:
1) My Gamecube controller is interfering with the Wii somehow.
2) The port I've plugged the controller into is interfering with the Wii somehow.
3) The AC adapter is busted.
4) Something is wrong internally inside the Wii.
So, I'm going to test just leaving it on overnight with no controllers, etc., in order to isolate the problem, but I'd still like opinions on what else can be done or if anyone else here has had this problem before.